www.antiaction.com / java / critical

Semaphores for use where tight resource control is needed.

Version:
1.00

License:

This package is distributed under the Free software Foundation's (FSF) General Public License (GPL).

Download:

critical.jar
critical-docs.tar.gz
overview-summary.html

Overview:

Semaphores are an extension of the java synchronization framework. In actuallíty the classes are wrapped around some datastructures and synchronized methods.

The main purpose of a semaphore is to restrict access to some critical region in a multithreaded program. Access can be mutually exclusive, resource determined or access determined. This package implementes 3 kinds of semaphores.

Mutex:

Restricts access to one thread at a time wirh support for nesting. Works like basic synchronization. People used to working with lowlevel languages might find this class closer to home.

Multex:

Allows for resource based multithreaded access to data. Access is allowed as long as there is at least one free resource. Possible use could be in a Provider/Consumer framework.

RWLock:

Enforces simultanious read access but exclusive write access.

Email:

Feedback should be sent to nclarke@diku.dk.